title: IQGAP-related Rng2p organizes cortical nodes and ensures position of cell division in fission yeast.
abstract: Correct positioning of the cell division machinery is crucial for genomic stability and cell fate determination. The fission yeast Schizosaccharomyces pombe, like animal cells, divides using an actomyosin ring and is an attractive model to study eukaryotic cytokinesis. In S. pombe, positioning of the actomyosin ring depends on the anillin-related protein Mid1p. Mid1p arrives first at the medial cortex and recruits actomyosin ring components to node-like structures, although how this is achieved is unknown. Here we show that the IQGAP-related protein Rng2p, an essential component of the actomyosin ring, is a key element downstream of Mid1p. Rng2p physically interacts with Mid1p and is required for the organization of other actomyosin ring components into cortical nodes. Failure of localization of Rng2p to the nodes prevents medial retention of Mid1p and leads to actomyosin ring assembly in a node-independent manner at nonmedial locations. We conclude that Mid1p recruits Rng2p to cortical nodes at the division site and that Rng2p, in turn, recruits other components of the actomyosin ring to cortical nodes, thereby ensuring correct placement of the division site.
authors.affiliation: Temasek Life Sciences Laboratory, The National University of Singapore, 1 Research Link, Singapore 117604, Singapore.
authors.forename: Anup
authors.initials: A
authors.lastname: Padmanabhan
authors.forename: Kavya
authors.initials: K
authors.lastname: Bakka
authors.forename: Mayalagu
authors.initials: M
authors.lastname: Sevugan
authors.forename: Naweed I
authors.initials: NI
authors.lastname: Naqvi
authors.forename: Ventris
authors.initials: V
authors.lastname: D'souza
authors.forename: Xie
authors.initials: X
authors.lastname: Tang
authors.forename: Mithilesh
authors.initials: M
authors.lastname: Mishra
authors.forename: Mohan K
authors.initials: MK
authors.lastname: Balasubramanian
mesh_terms: D000205:Actomyosin / Q000378:metabolism*; D019943:Amino Acid Substitution; D015153:Blotting, Western; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D002455:Cell Division / Q000502:physiology*; D003598:Cytoskeletal Proteins / Q000378:metabolism; D020690:GTPase-Activating Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D047468:Immunoprecipitation; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D012568:Schizosaccharomyces / Q000502:physiology*; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D017422:Sequence Analysis, DNA; D059008:Time-Lapse Imaging
chemical_list: D018797:Cell Cycle Proteins; D003598:Cytoskeletal Proteins; D020690:GTPase-Activating Proteins; C489694:Mid1 protein, S pombe; C114172:Rng2 protein, S pombe; D029702:Schizosaccharomyces pombe Proteins; C513274:cdc4 protein, S pombe; D000205:Actomyosin